Growth Abnormalities

Question 1

Most notable time for physical growth & ↑ in complexity of function

Answer 1

0-5 Years Old

Question 2

Brain grows to 2/3 of the adult brain size
by age _____

Answer 2

2½–3 years

Question 3

Identifying disturbances in development
during these early years is critical because time sensitive interventions may be instituted to address developmental issues

Answer 3

Ages 2-5

Question 4

Concerns with 2000 growth charts

Answer 4

2000 growth charts use NHANES data (1960’s-1990s) which compares current childs weight status to a time before the current obesity epidemic

Question 5

CDC growth charts

Answer 5

• 16 charts (8 for boys, 8 for girls): Ability to plot head circumference, height, weight, BMI and (in some cases) compare these to one another

Question 6

A child’s growth & height potential is determined largely by _____

Answer 6

genetic factors

Question 7

Most children achieve an adult height within ____ of
the midparental height

Answer 7

8 cm
* Target (midparental) height of a child =
* Mean parental height + 6.5 cm for boys
* Mean parental height – 6.5 cm for girls

Question 8

Bone Age

Answer 8

• Radiograph of the left hand & wrist
• Atlas of Skeletal Maturity, Greulich & Pyle
• Delayed or advanced bone age is NOT diagnostic
  of any specific disease
• Skeletal maturation determines remaining
  growth potential
• Allows prediction of adult height

Question 9

Normal vs. Pathologic Short Stature

Answer 9

Normal: Familial short stature, constitutional growth delay
Pathologic: Growth hormone deficiency,
Intrauterine growth restriction, Short stature associated w/ syndromes, Achondroplasia

Question 10

Familial Short Stature growth

Answer 10

• Normal birth weight & length in the first 2 years of life
• Linear growth velocity decreases as they near their genetically determined percentile
• Once the target percentile is reached, Resumes normal linear growth parallel to the growth curve, Usually 2 to 3 years old

Question 11

______ are consistent with chronologic age

Answer 11

Skeletal maturation & timing of puberty

Question 12

Constitutional Growth Delay

Answer 12

● Growth pattern similar to those with familial short stature EXCEPT
* Children follow a growth percentile that is below what is expected
based on parental heights
* Delay in skeletal maturation & the onset of puberty
● Growth continues beyond the time the average child stops growing
* Final height is appropriate for target height

Question 13

We usually refer to these patients as being “late bloomers”

Answer 13

Constitutional Growth Delay

Question 14

Growth Hormone Deficiency

Answer 14

Anterior Pituitary Gland → Human Growth Hormone (GH)
* Secretion stimulated by Growth Hormone Releasing Hormone (GHRH)
* Secretion inhibited by somatostatin
* GH is secreted in a pulsatile pattern (testing is problematic)

Question 15

Growth hormone deficiency (GHD) is characterized by _____

Answer 15

decreased growth
velocity and delayed skeletal maturation in the absence of other explanations

Question 16

____ is the MOST COMMON deficiency state

Answer 16

Idiopathic GHD

Question 17

Infants with GHD typically have ____

Answer 17

normal birth weight w/ slightly reduced
length

Question 18

Common 1st step evaluating for GHD

Answer 18

Serum concentrations of IGF-1 reasonably correlate to GH secretion & action in an adequately nourished child

Question 19

Physical Exam Findings of GHD

Answer 19

• Hypoglycemia: Often associated with pituitary deficiencies
• Microphallus: Newborn males with gonadotropin & GH deficiency
• Many GH deficient children have excess truncal adiposity
• Isolated GHD & hypopituitarism may be unrecognized until late in infancy or childhood

Question 20

Imaging that should be done to patients with GHD

Answer 20

All patients diagnosed with GHD should have an MRI of the hypothalamus and
pituitary gland to evaluate for a tumor prior to starting therapy

Question 21

Growth Hormone Deficiency Treatment

Answer 21

• Subcutaneous Recombinant GH
• SQ daily injection
  Expensive

Question 22

Who is GH deficiency treatment indicated for

Answer 22

• Chronic renal failure
• Girls with Turner syndrome
• Prader-Willi syndrome
• Noonan’s syndrome
• Children born small for gestational (SGA) who fail to demonstrate catch-up growth by age 4
• Children with idiopathic short stature: Final height ~5–7 cm taller in this population

Question 23

SGA infants

Answer 23

• Birth weight and/or length <3rd
  percentile
• Includes constitutionally small
  infants & infants with IUGR

Question 24

If mild SGA/IUGR and no fetal abnormalities, may exhibit catch-up growth during the _____

Answer 24

first 3 years

Question 25

Small for Gestational Age/Intrauterine Growth Restriction causes

Answer 25

* Poor maternal environment * Intrinsic fetal abnormalities * Congenital infections * Fetal malnutrition

Question 26

In contrast to children with constitutional growth delay, SGA/IUGR have _____

Answer 26

skeletal maturation that corresponds to chronologic age or is only mildly delayed.

Question 27

Short stature is associated with many syndromes, including:

Answer 27

1. Turner Syndrome 2. Prader-Willi Syndrome 3. Down Syndrome

Question 28

Any girl with unexplained short stature for family → _____

Answer 28

Chromosomal evaluation (turner syndrome)

Question 29

Most common form of inherited disproportionate short stature

Answer 29

Achondroplasia (Dwarfism) * Autosomal dominant

Question 30

Etiology of Achondroplasia (Dwarfism)

Answer 30

* Autosomal dominant: 80% of cases result from new mutations. * Pathogenic variants in the fibroblast growth factor receptor 3 (FGFR3) gene * Mutation disrupts chondrocyte proliferation & differentiation, disrupting growth plate structure

Question 31

Clinical presentation Achondroplasia (Dwarfism)

Answer 31

* Disproportionate short stature * Short limbs w/ redundant skin folds * Macrocephaly * Normal-sized trunk * Limited elbow extension * Genu varum * Large head with frontal bossing (rounded prominence) * Midface hypoplasia * Trident configuration of hands * Thoracolumbar gibbus (kyphosis) in infancy * Exaggerated lumbar lordosis

Question 32

Diagnosis of Achondroplasia (Dwarfism)

Answer 32

* Prenatal ultrasound: fetus with short stature & limb foreshortening, Macrocephaly * Imaging: X-ray & baseline MRI or CT of brain * Genetic testing: Fibroblast growth factor receptor-3 (FGFR3) gene mutations confirm diagnosis

Question 33

Achondroplasia (Dwarfism) complications

Answer 33

* Speech development problems * Teeth crowding * Sleep Apnea * Pneumonia

Question 34

Psychosocial Short Stature (Psychosocial Dwarfism)

Answer 34

* Growth impairment associated with emotional deprivation * Under-nutrition probably plays a role as well

Question 35

Is GH therapy used in Psychosocial Short Stature?

Answer 35

* GH secretion in children with psychosocial short stature is diminished * GH therapy is usually not beneficial

Question 36

How can psychosocial short stature be improved?

Answer 36

A change in the psychological environment at home improves: * growth * GH secretion * personality * eating behaviors

Question 37

Growth Hormone Excess

Answer 37

*Excessive GH secretion is rare & generally associated with a functioning pituitary adenoma *GH excess leads to gigantism → if the epiphyses are open (before puberty) *GH excess leads to acromegaly → if the epiphyses are closed (After puberty)

Question 38

Precocious Puberty

Answer 38

Tall stature for age or rapid growth *Typically associated with early signs of puberty & advanced bone age *Patients can be tall for age, but they do not achieve a taller final height than would be genetically & phenotypically expected

Question 39

History workup for growth

Answer 39

* The upper limit of acceptable height in both sexes has increased over time * Concerns about excessive growth in girls are less frequent than in the past * History of chronic illness * Medications * Birth weight & height, pattern of growth since birth * Family history & family growth patterns, growth curves

Question 40

Physical exam for assessing growth

Answer 40

* Height, weight, head circumference * Pubertal (Tanner) stage, & assessment of skeletal maturation allow estimation of final adult height * Dysmorphic features, body segment proportion, & psychological health. * Child with poor weight gain as the primary disturbance, a nutritional assessment is indicated.